Using Decision Tables for gathering requirements and development.

We are in the IT business, and a lot depends on how requirements are gathered. If we as IT Gurus try to implement a technology and ignore the requirements, then we have failed.

Our employers and clients are not interested in the latest technology, but they are rather interested in delivering the functionality their requirements dictates.

There are many ways to document requirements and there are times where you have to be innovative on how to document your client’s wishes and dreams. The better you are in this at the beginning, the better the final product will look at the end of the project.

One of the techniques I used many times to document and code requirements is Decision Tables.

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Java and Oracle : JDBC Layers and Connection types

I know no body does that, but I did it anyway :

I read through the JDBC connection types “http://download.oracle.com/javase/6/docs/technotes/guides/jdbc/getstart/intro.html#1019423” and thought I summarize the deferences between JDBC drivr types in this diagram:

Diagram Showing Layers of JDBC and Types with Oracle drivers

In short, there are 4 types of JDBC Connection, but only two are important from my experience:

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XML tutorial in 100 minutes

Time for another tutorial: XML in 100 minutes.

XML today is a vital technology in contemporary organizations, it is widely used to transfer data between applications and other uses.

Knowing XML for today’s IT Gurus is as important as Unix and SQL skills. Many Applications requires XML know-how.

This short guide to XML is only an fast introduction to XML, later tutorials will follow about the individual subjects in XML, like XSLT, SOAP …etc.

The tutorial is available here in PDF, HTML and Adobe-Flash Formats

One of the slides has an overview of XML technologies:

XML at a glance

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Java Troubleshooting: Application running inside Glassfish, unable to call a webservice

Flash Forward:  3 days already trying to troubleshooting the java code for “PrivilegedActionException” Exception , it turns out it is one parameter in Glassfish that needs to be properly adjusted.

Lets go back from the beginning: 3 days ago I was writing a JEE enterprise applciation , simply  a webpage that retrieves data from a DB2 database and then based on a user’s choice it call a webservice for some of the records in the result-set.

I followed GlassFish-Developer’s-guide to call an WS-RPC webservice. the server providing this WS-RPC is somewhere located inside our enterprise network.

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Oracle Virtual machine “OTN Developer Days” appliance.

If you are a developer and need your own Oracle environment to try out and test ideas without disrupting your main development environment, then I propose using a Virtual Machine with Developer Days appliance.

Choose what type of environment you want from this link and start following the instructions. I prefer the Developer Days appliance , since it requires reasonable resources and more related to my work. This virtual Machine contains:

• Oracle Enterprise Linux 5
• Oracle Database 11g Release 2 Enterprise Edition
• Oracle TimesTen In-Memory Database Cache
• Oracle XML DB
• Oracle SQL Developer
• Oracle SQL Developer Data Modeler
• Oracle Application Express 4.0
• Oracle JDeveloper
• Hands-On-Labs (accessed via the Toolbar Menu in Firefox)

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